Vehicle parts such as engines and transmissions are often used with various oils or other internal fluids. Various filters are known to remove contaminants or other materials from the fluids. In the case of transmissions, for example, filters having a housing that encloses a filter media such as a felt-like media are used, with the fluid passing through the media under pressure or suction applied to the filter on the inlet or outlet side.
An example of a filter is described in US20120012517A1.
When the fluid is at a colder temperature, some fluids become highly viscous and thus may create a large pressure drop compared to warm operation.